Snowmobile Arctic Cat (2008 year). Manual - part 41

2-101

2

CM150

14. Lift the pistons clear of the connecting rods and

remove the small-end connecting-rod bearings

(account for two washers); then remove the piston

rings. Keep each piston with its rings; keep each

piston pin and bearing together as a set.

CM151

„NOTE: Place a suitable length of rubber hose
around the connecting rods. This will prevent the
connecting rods from damaging the crankcase.

15. Remove the cap screws securing the intake

flanges; then remove the intake flanges and reed

valve assemblies.

CM152

16. Remove the lower union cap screw securing the

lower check valve assembly to the crankcase; then

remove the two screws securing the oil-injection

pump to the crankcase. Remove the pump,

retainer, and O-ring and account for the two gas-

kets from the lower union.

CM153A

CM154A

17. Remove the four cap screws securing the thermo-

stat cap; then remove the cap, gasket, and thermo-

stat.

CM155A

„NOTE: For assembling purposes, note that the
positioning of the bypass/check valve is directed
up.

! CAUTION

DO NOT use any type of punch to drive the piston
pin free of the piston; damage may result. Use a pis-
ton-pin puller only.

2-102

CM157A

18. Remove the six screws securing the water pump

cover to the crankcase and remove the cover.

Account for the O-ring gasket and the alignment

pins.

CM156A

19. Remove the cap screw securing the water pump

impeller; then slide the impeller free of the shaft.

20. Prior to turning the engine upside down on the 800

cc, remove the two crankcase cap screws (A) from

the water pump side of the engine; then remove

the two cap screws (B) from the magneto housing.

On the 1000 cc, remove the one crankcase cap

screw (C) located above the thermostat housing.

742-198B

742-197B

21. Turn the engine upside down on support blocks,

cut the cable tie, and remove the coolant tempera-

ture sensor switch.

22. With its bottom side up on two support blocks,

remove the cap screws securing the crankcase

halves.

23. Separate the crankcase halves by installing two

crankcase cap screws in opposite corners leaving

the heads approximately 6 mm (1/4 in.) out. Using

a plastic hammer and lifting on the ends of the

crankshaft, tap on each cap screw head until the

case halves separate. Remove the cap screws.

CM158

24. Lift the bottom half of the crankcase off the top

half.

25. Lift the crankshaft free from the top half of the

crankcase and slide the crankshaft oil seals off the

crankshaft. Account for the C-ring. Remove the

bearing retaining pins and account for the crank-

case dowel pins.

! CAUTION

DO NOT drive any tool between halves to separate
the crankcase. Damage to the sealing surfaces will
result.

! CAUTION

Care must be taken to not allow the connecting rods
to drop onto the sealing surface of the bottom case
half.

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2

„NOTE: The end bearings are not pressed onto
the crankshaft. After removing the seals, use care
not to allow the bearings to slide off the crank-
shaft.

26. Remove the oil-injection pump/water pump drive-

shaft from the lower crankcase half. Account for

the thrust washer on the outer end of the shaft.

CM159A

„NOTE: Do not replace the inner seals unless the
water pump shows signs of leaking coolant out of
the small bleed hole in the bottom half of the
crankcase. If a water pump seal is to be replaced,
use the Water Pump Bearing and Seal Tool Kit.

27. Place the crankcase on the bench with the water

pump side down. Using the long seal driver, drive

the mechanical water pump seal from the crank-

case.

FC036

28. Using a pair of snap ring pliers, remove the snap

ring securing the inner seal in the crankcase.

29. Using the hooked end of the tool, pull the inner

seal free of the crankcase.

30. Using the hooked end of the tool, pry the seal ring

from the backside of the water pump impeller.

AN327D

Servicing Top-Side 

Components 

Many services can be performed without removing the

engine. Some components may vary from model to

model. The technician should use discretion and sound

judgment when removing and installing components.

„NOTE: Some photographs used in this sub-sec-
tion are used for clarity purposes only and are not
designed to depict actual conditions.

REMOVING TOP-SIDE 
COMPONENTS

To access top-side components, use the following pro-

cedure:

1. Disconnect the exhaust temperature sensor; then

cut the cable tie securing the sensor harness to the

APV cable.

2. Remove the expansion chamber and resonator and

account for the springs, hairpin clip, and the tab

washer; then remove the exhaust manifold.

CM186

3. Drain the engine coolant (see Liquid Cooling Sys-

tem - Section 3).

4. Remove the cap screws securing the side-plate

brace and steering support to the chassis; then

remove the side-plate brace.

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CM133A

CM132A

5. Remove the cap screws securing the APV assem-

blies to the cylinders; then remove the APV

assemblies and set them aside.

„NOTE: For installing purposes, note that the APV
exhaust valves and gaskets are directional.

CM187

„NOTE: At this point on the 800 cc, remove the
spark plugs (A) to gain access to the cylinder head
cap screws; then disconnect the knock sensor
plug-in (B).

CM188A

6. Remove the cap screws securing the cylinder head;

then lift the front of the head and remove the O-rings.

CM189

CM190

7. Carefully lift and turn the cylinder head to gain

access to the hose clamp securing the coolant hose

to the cylinder head; then loosen the clamp.

Remove the coolant hose and breather hose con-

nected to the cylinder head.